<!DOCTYPE HTML PUBLIC "-//W3O//DTD W3 HTML 2.0//EN">
<!Converted with LaTeX2HTML 95 (Thu Jan 19 1995) by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds >
<HEAD>
<TITLE> Program  vectopt</TITLE>
</HEAD>
<BODY>
<meta name="description" value=" Program  vectopt">
<meta name="keywords" value="html">
<meta name="resource-type" value="document">
<meta name="distribution" value="global">
<P>
 <BR> <HR><A NAME=tex2html268 HREF="node11.html"><IMG ALIGN=BOTTOM ALT="next" SRC="next_motif.gif"></A> <A NAME=tex2html266 HREF="node8.html"><IMG ALIGN=BOTTOM ALT="up" SRC="up_motif.gif"></A> <A NAME=tex2html260 HREF="node9.html"><IMG ALIGN=BOTTOM ALT="previous" SRC="previous_motif.gif"></A> <A NAME=tex2html270 HREF="node1.html"><IMG ALIGN=BOTTOM ALT="contents" SRC="contents_motif.gif"></A>   <A HREF="node28.html#SectionIndex"><IMG ALIGN=BOTTOM ALT="index" SRC="index_motif.gif"></A> <BR>
<B> Next:</B> <A NAME=tex2html269 HREF="node11.html"> Program  matropt</A>
<B>Up:</B> <A NAME=tex2html267 HREF="node8.html"> Optimizing and Example </A>
<B> Previous:</B> <A NAME=tex2html261 HREF="node9.html"> Program  lastest</A>
<BR> <HR> <P>
<H2><A NAME=SECTION00052000000000000000> Program  vectopt</A></H2>
<P>

<P>
<H6><A NAME=SubsectionVECTOPT>&#160;</A></H6>
<P>
The program <tt> vectopt</tt> could be applied to check the efficiency
of several implementations of the vector operation:

<PRE>  &lt;Vector 1&gt; += &lt;Vector 2&gt;.
</PRE>

It produces results like these:

<PRE>Results:    (for dimension 1000000, cycles 100)
--------

 implementation    CPU time
-----------------------------------------
    LASPack       2.518e-01 s = 100.0 %
       1          3.548e-01 s = 140.9 %
       2          3.196e-01 s = 126.9 %
       3          2.481e-01 s =  98.5 %
       4          2.392e-01 s =  95.0 %
       5          2.395e-01 s =  95.1 %
-----------------------------------------
</PRE>
<P>
For details of the implementations look at the file
<tt> laspack/examples/vectopt/testproc.c</tt>.
The current <tt> LASPack</tt>
  version corresponds to the implementations 2 and 3
depending on the computer architecture.
They are, in comparison with <tt> LASPack</tt>
 , simplified and 
can therefore be a little faster.
<P>

<BR> <HR>
<P><ADDRESS>
Tomas Skalicky (skalicky@msmfs1.mw.tu-dresden.de)
</ADDRESS>
</BODY>
</BODY>
